I used to work at a local shop that specialized in LS motors (primarily Vettes). We’d always fill the cars up with Chevron but at the time I didn’t know why, just that it was a better quality gas.
So for those of you that don’t know about gas quality and detergents this guy explains it pretty well…
What I Just Learned About Gasoline, And How Did I Never Know About This Before??
I used to have a '91 'vette. It would not run right on Chevron gas. Any other station was fine.
We didn’t do work on anything older than the C5s which were the first vettes with the LS series motors, the L98 is very different motor. It’s kind of like comparing the SBF used in the 94 mustangs to the Coyote used in the modern ones.
It is possible that the additives they used affected that motor differently, but I really have no experience with the L98, just the LS motors, and we ran all the cars on Chevron whether they had a cam, heads & cam, or cam & supercharger.
There was a TT 7.0L car that came in occasionally with about 1100rwhp, but I can’t remember if it ran with meth injection or race gas (it was like 8 years ago so my memory is a bit fuzzy).
There is one budget tier major name that is not listed in the top tier gasoline site. As I understand it, they found a really cheap detergent that passes the government detergent test on the antique test engine, but actually causes more deposit build up on intake valves and combustion chambers than no detergent, when used in most modern engines.
I’m guessing you’re talking about RaceTrac… as if the bathrooms alone weren’t enough reason to go to QT.
edit: and free air.
My mother in law worked at chevron chemical for 30 some years. All gas is the same, the difference is the additives in it. The cheaper the gas the more pure the gas, no additives.
I can’t speak for the refinement process, I’m sure there are standard for the actual gas refinement, but according to carfax that seems to be the case.
Not really related but is there anyone at the space who runs straight ethanol?
A few of the guys in DFW5.0s do as it lends itself to high boost pressures, but I’ve read that it can corrode the engine relatively quickly
That article is full of inaccuracies and is pretty useless.
Are you going to refute any of the “inaccuracies” and provide references, or are you just going to make an unsupported claim?
Not intended to offend you Corey.
The article from Carfax (that alone should be a red flag) is mostly rubbish, especially the part on fuel injection. Plus the owner of the MDX asking if “poor gasoline” could have caused his engine problems. Too many variables could cause engine problems - not too mention dishonest service garages / dealers etc. It is always easier to place blame on something else.
Most of these articles are written by journalists and rarely fact checked.
Everyday stock(consumer) street cars are not the same as a custom built car (track,drag,show, etc) and shouldn’t be used in a comparison. Apples to apples etc.
But if you would like a few facts regarding the article:
Fuel injection for mass produced(keyword is “mass”) cars was found on European models in the late 1960s - not the 1980s as the article states.
Direct injection - interesting term there. True direct injection bypasses the intake manifold. Injection behind the intake valves at the individual ports is NOT direct injection.
European manufacturers required higher octane - not “top tier” retail branded fuel. Octane level is NOT the same as how much detergent is in a fuel.
Ethanol is the worst thing the EPA has done to automobiles (speaking of the EPA - I cannot think of anything they have done “for” the industry in a positive way, that hasn’t cost the end user (consumer) countless dollars.
Give a listen to the AM radio program “Wheels” with Ed Wallace on 570 AM on Saturday mornings from 8 AM to 1 PM. He has been in the car industry for 40+ years and has written several articles about the differences in gasoline. He flatly states that new cars with computer sensors will accommodate different qualities of gasoline automatically and also points out that almost all gasoline is made in the same place. When callers ask if they should buy a particular brand of gasoline or only high octane he tells them that it makes no difference. He does stress that ethanol is not only bad for gasoline engines but that it is counterproductive, since it uses more energy to make than it produces.
Terrence, I’d like to have a count of how many Makers are up that early on a Saturday?
Modern cars do have sensors - knock sensors, among others (typically) to sense detonation and adjust timing & fuel to handle lower octane fuels.
Detergents have zero to with detonation.
Two things that begin with “E” and are terrible for the automotive industry are Ethanol and the EPA. Ethanol is a knee jerk band aid that causes more problems and expense to the consumers in order to make the environmentalists “feel” better.
Well, I was up that early once driving a company truck that only had an AM radio. That’s how I know about it, LOL. I think he is set up to stream audio, though.
I read somewhere that certain places, Racetrack was specifically mentioned,
tend to buy gas that’s been stored for a few months. This settling
increases the amount of sediment and water in it, making it more likely to
cause damage.
I can find backing only for the storage causing increases and places
selling damaging gas of that nature, so take with a grain of salt.
Sincerely,
Tim Nielsen
I have heard a different story.
While the gasoline as distributed is shared across many brands, the detergent package, which is a fairly small percentage of the gasoline is brand specific, and is a non trivial expense. The common stock accounts for all the parameters that a modern engine can adjust for. The detergent package is what helps prevent carbon soot and other build up on the valves, combustion chamber, and to an extent ring grooves. These are all things that the engine can’t adapt to. These are all things that happen slowly, over many tanks, and you can’t point to what caused the issue.
Now since these detergent packages play such an important role in long term performace, you would think there would be some federal regulation on them. It turns out that there is. There is a federal standard that requires a test cycle in a very specific model, antiquated carbureted engine. For some reason, I’m thinking it was from the 40s. A freshly rebuilt motor is run under specific conditions for a specified number of hours, torn down, and the deposits measured again the limits.
Allegedly, there is package that is slightly modified industrial waste, that works beautifully in the obsolete test engine, but when lab tests against modern engines are performed, result in more deposits than not having a detergent at all. So anyone using this detergent meets federal requirements for a really low price, since it is basically waste material, and the consumer gets a messed up engine over time.
My two cents worth. I asked my mechanic about about fuel injector cleaners during the last major mainetnance work (Cam belt, shocks, brakes, ignition harness, etc). He said to fill the tank with MID-GRADE not Premium about every 4 to 5 tankfuls to kept the fuel system clean.
Like many I’ve read various things on top tier vs non-top tier (being cheap I buy gas a lot at COSTCO which is a top-tier source). Looked up something Top Tier Gas – Medicine for Your Engine. Article is by CARFAX, which doesn’t sell or market gasoline so in IMHO is less likely to be biased one way or the other. A short article and does provide links to sources quoted that have opposing views - which at least minimizes bias.
Gasoline is mainly pumped through common pipelines from refineries for both cost and safety reasons to distribution points where the specific company additives are added (Chevron, Mobil, whoever) and is then distributed by trucks to stations. You can see this at those distribution points because trucks from all the companies go there to fill up.
I will not try to tell you whether to use top-tier gasoline or not, but I WILL say this article (as linked by @photomancer ) is remarkably misleading and mis-informative at its base, which makes one distrust the higher-level purpose.
Since I presume someone will ask how, here we go.
As already enumerated, spark-ignition engines generally did not use “direct fuel injection” in the 1980s or 1990s. Though earlier fuel injection systems did use direct injection, it was relatively rare, if not non-existent from 1975ish-1996, since end of the “kugelfischerr” era, which was then only on higher end European cars. (there were others, to be fair, but none were considered “successful” and only approximated “mass produced”). These systems DID use direct injection of gasoline into the combustion chamber (in some instances), which leads me to my second beef: the illustrations.
The illustrations show side-port injected systems, which again, have not been part of the picture since the 1970s. Pretty well all gasoline injection systems, since the demise of the earliest of forays e.g. Kugelfischer, have directed their spray through the cylinder head area, either through throttle bodies, or ports in the intake manifold. More recent systems which DO employ direct injection, still send the fuel in, largely, through the head and not the block.
So, right off the bat, I’ve got major beef with the words they choose, and the pictures they use, since it makes it appear to have been produced by a team with little expertise and little fact-checking. So I have to question everything else about the article.
“Top Tier” fuel may well be the best thing for your engine, but this article does the marketing more harm than good, in my opinion.
Jast - don’t you like the diagrams for elementary school age children of a generation ago? 
When I wrote earlier about “mass produced” cars with port injection - I was referring to VW in 1968 with it’s electronic fuel injection with 4 individual injectors (granted this was only on the type 3 models). In 1975 all US sold VW’s had fuel injection - some w/ electronic infectors and some w/ mechanical injectors.
On a more modern note - today’s direct injection - is causing more problems for the consumer that detergents in any fuel cannot cure at all.